Hyperprolactinaemia
Definition
Hyperprolactinemia is defined by the increased secretion of prolactin by the anterior pituitary gland.
Aetiology
Physiological causes: [Ref1][Ref2]
- Pregnancy
- Lactation (breastfeeding)
Pathological causes: [Ref1][Ref2]
| Category | Important causes |
|---|---|
| Medication causes | Most commonly secondary to dopamine antagonists:
|
| Hypothalamic-pituitary causes |
|
| Systemic causes |
|
Key physiology concept:
- Prolactin is secreted by the anterior pituitary gland
- Dopamine (secreted by the hypothalamus) inhibits prolactin secretion
- Thus, any cause of dopamine antagonism or pituitary stalk damage / compression will result in increased prolactin secretion (from disinhibition)
Clinical Features
Main effects of hyperprolactinaemia:
- Stimulates lactation
- Inhibit gonadotropin secretion (LH, FSH, testosterone, oestrogen)
| Women | Men | |
|---|---|---|
| Breast |
|
|
| Reproductive system |
|
|
| Other | Osteoporosis (from only in prolonged, untreated cases) | |
Clinical features of the underlying cause may also be present, for instance:
- Pituitary adenoma: headache, bitemporal hemianopia
- Hypothyroidism features
Investigation and Diagnosis
A single measurement of serum prolactin (above the upper limit of normal) can diagnose hyperprolactinemia. [Ref]
Subsequent tests should be performed to look for the underlying cause: [Ref]
- Important initial actions
- Exclude pregnancy
- Medication review
- Tests
- Gonadotrophin levels (LH, FSH, oestrogen, testosterone)
- TFT
- Renal and liver function
- Pituitary MRI
Management
Treatment depends on the underlying cause of hyperprolactinaemia.
Main important ones: [Ref]
| Cause | Treatment |
|---|---|
| Drug-induced hyperprolactinaemia |
|
| Prolactinoma |
|
| Hypothyroidism |
|